Throughout this application various publications are referred to in parentheses. Full citations for these references may be found at the end of the specification. The disclosures of these publications are hereby incorporated by reference in their entirety into the subject application to more fully describe the art to which the subject invention pertains.
Liver biopsy is the gold standard for the evaluation of acute and chronic liver disease. Percutaneous liver biopsy (PLB) remains the preferred approach in most situations; however, transjugular liver biopsy (TJLB) (1) can be performed where there are contraindications to a percutaneous approach, such as coagulopathy, thrombocytopenia or ascites where PLB may be prone to bleeding (2-4). TJLB is considered safer in these situations since any bleed will most likely be intravascular.
However, TJLBs can be difficult, and there are potential complications. TJLB requires hepatic vein cannulation through which the biopsy specimen is obtained. Difficulties include negotiating a stiffened cannula into acutely angled hepatic veins; maintaining a stiff cannula in the hepatic vein during movement caused by the patient's respiration while avoiding injury of the hepatic vein/liver junction, and the need for two operators—one to hold the cannula and one to remove the biopsy specimen from the needle.
Biopsies performed directly through the inferior vena cava (IVC) from a jugular approach have also been described in instances when a hepatic vein could not be cannulated (5). Difficulties with this approach can include difficult jugular access and the need to traverse and exit the right atrium (RA) into the IVC.
The present invention provides procedures and devices for a transfemoral transcaval (TFTC) approach for liver biopsies that is expected to be safer, easier and more reliable than a transjugular approach.